The conventional motorcycle disk brake lock is generally composed of a main body and a locking member. The main body is provided with a slot for receiving therein a motorcycle disk brake. The locking member comprises an inner side capable of moving in a reciprocating manner and across the slot, and an outer side capable of being controlled by a key. In operation, the edge of the disk brake is placed in the slot before the inner side of the locking member is pushed across the two opposite inner walls of the slot such that the inner side of the locking member is put through a heat-radiating hole of the disk brake. The disk brake lock can be disengaged with the disk brake by using a designated key to rotate the outer side of the locking member so as to cause the inner side of the locking member to be forced out of the slot by a spring.
Such a prior art motorcycle disk brake lock as described above is defective in design in that a specific tool can be inserted into the key hole of the outer side of the locking member to push away the retaining pins of the locking member so as to release the inner side of the locking member. In other words, the prior art motorcycle disk brake lock can be tampered with easily by an unauthorized person.